There is in existence a blow molded polyester container of the type specifically constructed for filling with a hot product. Such a container has a generally cylindrical body with a major portion of that body being in the form of a label receiving portion and wherein the label receiving portion is provided with a plurality of circumferentially spaced expansion panels having therebetween a vertical reinforcing rib. While the container otherwise performs satisfactorily, it has been found that unexpectedly there is a deformation of the container body within the label receiving portion thereof at the ends of the reinforcing rib. Why this distortion occurs is not clear.